Sudden cardiac death (SCD) is a major public health problem that accounts for more than half of all cardiovascular deaths. SCD takes the lives of approximately 450,000 people in the United States each year, more than lung cancer, breast cancer, stroke, and AIDS combined. Most cases of SCD are due to ventricular arrhythmias and there is often an element of underlying ischemic heart disease. Ventricular tachycardia (VT) and ventricular fibrillation (VF) are different types of ventricular arrhythmias. VT is an abnormally fast ventricular heart rhythm which is, by itself, typically not fatal. VF is a chaotic ventricular heart rhythm which produces little or no net blood flow from the heart, such that there is little or not net blood flow to the brain and other organs. VF, if not terminated, results in death. Patient groups most at risk of ventricular arrhythmias leading to SCD include those with an acute or chronic myocardial infarction. Accordingly, deaths from SCD may be lowered by preventing the specific heart rhythm disturbances (ventricular arrhythmias) associated with it.
Different treatment options exist for SCD. The most common treatment includes implantable cardiac defibrillators (ICD) and drug therapy. Current ICD technology, however, only provides for the detection and recognition of an arrhythmia based on the sensed heart rate once it has already started. This leaves very little time to protect the individual from sudden cardiac death. Although there have been several attempts at developing new technology for predicting the onset of a cardiac arrhythmia, many of these methods and systems appear to rely primarily on events occurring within the heart, such as sensed heart rate and electrocardiography (ECG). For example, U.S. Pat. No. 6,308,094 discloses a method and device for predicting cardiac arrhythmias by gathering and processing electrocardiographic data, such as intervals between heart beats (RR-series) or other heart signals, to predict the occurrence of a cardiac arrhythmia. U.S. Pat. No. 6,516,219 discloses a method and apparatus for forecasting arrhythmia based on real-time intact intracardiac electrograms.
There currently exists no method of predicting cardiac arrhythmias well in advance of their occurrence that would allow for the institution of preventive and/or ameliorative therapy. A method and kit for predicting the occurrence of arrhythmias that allows preventive measures to prevent sudden cardiac death would thus represent a great advance in the art.